Various methods are known for forming a document file which has a front cover and a rear cover provided with a pocket. In one method, the pocket is connected to the cover with a pair of gussets which allow the pocket to expand to vary the capacity of the file. Gusseting involves expensive tooling and a document file formed by this method cannot be stored totally flat. Further, a glueing or welding operation is required to fix the pocket in the file. In another method, the pocket is formed by two or more flaps which are not held together with a resulting loss of security in retaining documents in the file. In another file, a pocket is formed by a side flap and a pair of end flaps which are held in position by elastic bands when the file is closed.